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MFWP 2010 Section 10 Report Kootenai River White Sturgeon

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MFWP 2010 Section 10 Report Kootenai River White Sturgeon Kootenai River White Sturgeon Acipenser transmontanus : 2009-2010 Investigations in Montana by Brian Stephens and Ryan Sylvester Montana, Fish, Wildlife and Parks Libby Area Office Section 10(a)(1)(A) Permit TE-210255-0 January 2011 1 Table of Contents Table of Contents ...................................................................................................................................... 2 Abbreviations and Acronyms ................................................................................................................... 3 List of Figures ........................................................................................................................................... 4 List of Tables ............................................................................................................................................ 6 Introduction ............................................................................................................................................... 7 Methods .................................................................................................................................................... 8 Results and Discussion ........................................................................................................................... 12 Total Catch .................................................................................................................................. 12 White Sturgeon ........................................................................................................................... 21 Recommendations ................................................................................................................................... 34 References Cited ..................................................................................................................................... 36 Appendices ............................................................................................................................................. 38 2 Abbreviations and Acronyms Abbreviation or Acronym Used Meaning or Description B.C. British Columbia CI Confidence interval cm centimeter CPUE catch per unit effort CSU largescale sucker BT bull trout ESA Endangered Species Act FL Fork length ft Foot or feet g gram ID Idaho IDFG Idaho Department of Fish and Game kg kilogram km kilometer KTOI Kootenai Tribe of Idaho m meter MFWP Montana, Fish, Wildlife and Parks mm millimeter MT Montana N Sample size NSQ northern pikeminnow ONC Oncorhynchus spp. PIT Passive integrated transponder RBT rainbow trout rkm river kilometer TL Total length U.S.A. United States of America USFWS United States Fish and Wildlife Service WCT westslope cutthroat trout WTSTRG white sturgeon yr year % Percent # number 3 List of Figures Figure 1. Map of 2009 sampling locations for white sturgeon in the Kootenai River, Montana from Kootenai Falls to the Montana-Idaho border. ................................................................................... 9 Figure 2. Map of 2010 sampling locations for white sturgeon in the Kootenai River, Montana from Kootenai Falls to the Montana-Idaho border. ................................................................................. 10 Figure 3. Species composition (percent of total catch) caught during sampling efforts for white sturgeon using baited setlines in the Kootenai River, Montana in 2009 and 2010. ....................... 12 Figure 4. Length frequency distribution of northern pikeminnow caught during setline sampling for white sturgeon in 2009 and 2010 in the Kootenai River, Montana. ............................................... 13 Figure 5. Length frequency distribution of largescale sucker caught during setline sampling for white sturgeon in 2009 and 2010 in the Kootenai River, Montana. ......................................................... 14 Figure 6. Length frequency distribution of rainbow trout, westslope cutthroat trout, and rainbow X cutthroat trout hybrids caught during setline sampling for white sturgeon in 2009 and 2010 in the Kootenai River, Montana. ............................................................................................................... 15 Figure 7. Total catch by bait type during setline sampling for white sturgeon in the Kootenai River, Montana in 2009 and 2010. ............................................................................................................ 16 Figure 8. Total catch by species caught and bait used during setlines sampling in the Kootenai River, Montana from June to September 2009 and may though September 2010. ................................... 16 Figure 9. Total catch by hook size (%) during setline sampling for white sturgeon in the Kootenai River, Montana in 2009 and 2010. ................................................................................................. 17 Figure 10. Mean length (mm) of fish caught by hook size during 2009 setline sampling in the Kootenai River, Montana. Dots represent fish with lengths significantly different (outliers) than the mean length by hook size and are represented by white sturgeon or bull trout. ....................... 18 Figure 11. Mean length of fish caught by hook size during 2010 setline sampling in the Kootenai River, Montana. Dots represent fish with lengths significantly different (outliers) than the mean length by hook size and are represented by white sturgeon or bull trout. ...................................... 18 Figure 12. Total catch (number of fish) by hook size during setline sampling in the Kootenai River, Montana during 2009 and 2010. ..................................................................................................... 19 Figure 13. Total catch per line (number of fish) by sampling section during 2009 (retrospectively assigned) and 2010 sampling efforts for white sturgeon in the Kootenai River, Montana. ........... 20 Figure 14. Comparison of mean total length of common fish species captured during 2009-2010 setline sampling for white sturgeon and 2007-2009 IDFG and MFWP electrofishing data downstream of Kootenai Falls in the Kootenai River, Montana. ................................................... 21 4 Figure 15. Map of the two sturgeon capture locations between the Yaak River confluence (rkm 285.5; lower right) and near the Montana-Idaho border (rkm 276.1) during setline sampling from June to September 2009 in the Kootenai River, Montana. ......................................................................... 23 Figure 16. White sturgeon (#1) captured on September 1, 2009 in the Kootenai River, Montana. ...... 24 Figure 17. White sturgeon (#2) captured September 29, 2009 in the Kootenai River, Montana. ......... 25 Figure 18. Map of the four white sturgeon capture locations between Throops Lake (rkm 305.0) and Sturgeon Hole (rkm 306.5) during setline sampling from May to September 2010 in the Kootenai River, Montana. .............................................................................................................................. 27 Figure 19. White sturgeon (#1) captured July 14, 2010 in the Kootenai River, Montana. ................... 28 Figure 20. White sturgeon (#2) captured July 23, 2010 in the Kootenai River, Montana. ................... 29 Figure 21. Linear relationship between total length and weight for five white sturgeon captured in Montana during 2009 and 2010 with the estimated weight for one fish for which actual weight was not obtained. ............................................................................................................................ 29 Figure 22. White sturgeon (#3) captured August 31, 2010 in the Kootenai River, Montana................ 30 Figure 23. White sturgeon (#4) captured September 17, 2010 in the Kootenai River, Montana. .......... 31 Figure 24. Estimated annual growth rates with 95% CI for white sturgeon captured in Montana in 2009 and 2010 and in Idaho from 1990 – 2007 (KTOI 2007). ....................................................... 32 5 List of Tables Table 1. Sampling section numbers, section boundaries, and section lengths used for randomized sampling of white sturgeon in the Kootenai River, Montana in 2010. ........................................... 11 Table 2. Summary of lines, line hours, total catch (# of fish), and CPUE (catch/line and catch/line hour) by sampling section in 2009 and 2010 sampling. ................................................................. 19 Table 3. Growth estimates for the white sturgeon (#2) captured on September 29, 2009 by release cohort. Fork length instead of total length was used for growth estimates because the 2004 year class did not have total lengths reported in Ireland et al. 2002. ...................................................... 25 Table 4. Growth estimates for the white sturgeon (#1) captured on July 14, 2010 by release cohort. 28 Table 5. Growth estimates for the white sturgeon (#2) captured on July 23, 2010 by release cohort. 30 Table 6. Growth estimates for the white sturgeon (#4) captured on September 17, 2010 by release cohort. ............................................................................................................................................. 31 6 Introduction The Kootenai River in British Columbia (B.C.), Canada, and Idaho (ID) and Montana (MT), U.S.A. contains a unique landlocked population of white sturgeon Acipenser transmontanus that has been isolated from anadromous Columbia River populations
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